persuasiveness vs vagueness

persuasiveness

noun
  • The capability of a person or argument to convince or persuade someone to accept a desired way of thinking. 

vagueness

noun
  • Something which is vague, or an instance or example of vagueness. 

  • The condition of being unclear; vague. 

How often have the words persuasiveness and vagueness occurred in a corpus of books? (source: Google Ngram Viewer )